Features: This product is an industrial grade RS485 interfaces controlled 8-way Relay module with 8-way switching input, using Modbus RTU protocol, built-in power isolation, magnetic coupling isolation, and TVS protections circuits. This product is easy to operate and has the characteristics of fast communication speed, stability, reliability, and safety. It can be suitable for various industrial control equipment or applications with high communication requirements. It can provide stable isolation voltage, without the need for additional power supply at the isolation end. The integrated magnetic coupling isolation on theboard can be used for signal isolation, with high reliability, strong anti-interference, low power consumption, and board mounted self recovery fuses and TVS (transient voltage suppression tubes), Adopting a dedicated Relay driver chip with built-in freewheeling diode protections, the driving ability is stronge and stable. The switching input is equipped with bidirectional optocoupler isolation, supporting passive and active switching input Adopting high-quality Relay ABS protective case, convenient for installation and use, with case for safe external LED indicator light, convenient for viewing MCU status and signal transmission status Specifications: Material: Plastic Size：As Pictures Channel: 8CH Protocol：Adopting Modbus RTU protocol Interfaces:RS485 Package Includes: 1PC Modbus RTU 8CH Relay Module note: Due to the problems of lighting effectsand shooting angles, there will be certain tolerances in the product, please understand. Please allow 0-1cm error due to the manual measurment.